We stepped from the warmth of our home to the cold of a steady autumn rain. The boys abandoned their umbrellas and ran off to splash one another. But Grace

steadfastly held my hand while she sloshed through puddles and searched for worms.

Twelve years ago, when I first became a mother, I never considered that walking on a wet, rainy afternoon would be one of my duties. Now I began to contemplate this job and all it entailed. Rather than a static job description, this one changes on a daily basis.

I began motherhood as "Mama." While the rest of the world slept, I rocked my son. Family members said: "You'll spoil him," or "He'll be a Mama's boy."

I'd gaze down at his peaceful, sleeping face. No, I thought, I'm not spoiling him.

The word "Mommy" - wailed, whispered, or giggled - signaled a change in my role. I became a best friend, a cohort, and sometimes a disciplinarian as my child entered toddlerhood. A walking, talking little person ready to explore the world took the place of one who needed midnight feedings.

All too soon I had two sons and became just "Mom" - someone they needed privately, but not in front of their friends.

Nelson, my oldest child, asked me one morning if I would come to his basketball game after school. When I walked into the gymnasium, minutes before the game began, I called to him. His reaction startled me.

"Mom," he said sternly, "can we do this outside, please?" The moment we stepped beyond the scrutiny of his peers, he threw himself in my arms. Evidently he still wanted my hugs and encouragement, he just didn't want any witnesses.

I am fast approaching the "Mother" stage - the title I used to keep my own mother at bay during my teenage years. My new name will be spoken in a drawn-out way that makes the final "r" sound like a growl: Motherrr, to emphasize the fact that I, who was once capable of miraculous things such as baking cookies or coloring the sun yellow, cannot understand the rudimentary rules of what it's like to be a teenager.

But that title will also mean my children are preparing themselves for flight, and I'm their test run. We've left the bliss of unbounded oneness and entered the bittersweet joy of seeing that oneness fade as they learn to stand alone.

But, thankfully, they don't all reach that age at the same time.

• Julia Rosien lives in Kitchner, Ontario, with her husband and children.